The proposed experiments will describe the consequences of perinatal cannabinoid exposure on the development of the male reproductive system. The studies will also delineate the "critical periods" during sexual differentiation which may be particularly succeptible to cannabinoid influence. Finally, parallel observations on the immediate and long-term consequences of cannabinoid exposure on several parameters, including patterns of plasma hormones, steroid and gonadotrophin receptors, weights of testes and androgen-dependent target tissues, will permit the development of hypothesis concerning the mechanism of cannabinoid actions in altering male reproductive functions. These studies will provide a comparison of the effects produced by the major psychoactive component in marihuana, Delta-9-tetrahydrocannabinol (THC) with those of the nonpsychoactive cannabinol (CBN), at a variety of doses. These studies will also evaluate the possibility that social factors, such as housing with female conspecifics or sexual experience may be capable of attenuating some consequences of perinatal cannabinoid exposure. This information, together with evidence of specific cannabinoid-induced deficits within the reproductive system, will allow manipulations to reverse these cannabinoid effects. The results of these experiments will indicate the immediate and long-term consequences of cannabinoid exposure on the developing male mouse, as well as the potential for therapeutic intervention. Such information will suggest possible risks involved with marihuana use during pregnancy in the human.